137878021670401 has 4 divisors (see below), whose sum is σ = 137878069096404. Its totient is φ = 137877974244400.

The previous prime is 137878021670387. The next prime is 137878021670491. The reversal of 137878021670401 is 104076120878731.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 84178423014400 + 53699598656001 = 9174880^2 + 7328001^2 .

It is a cyclic number.

It is not a de Polignac number, because 137878021670401 - 2¹¹ = 137878021668353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (137878021670491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19045990 + ... + 25268671.

It is an arithmetic number, because the mean of its divisors is an integer number (34469517274101).

Almost surely, 2^{137878021670401} is an apocalyptic number.

It is an amenable number.

137878021670401 is a deficient number, since it is larger than the sum of its proper divisors (47426003).

137878021670401 is an equidigital number, since it uses as much as digits as its factorization.

137878021670401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47426002.

The product of its (nonzero) digits is 3161088, while the sum is 55.

The spelling of 137878021670401 in words is "one hundred thirty-seven trillion, eight hundred seventy-eight billion, twenty-one million, six hundred seventy thousand, four hundred one".